|MadSci Network: Microbiology|
Hi! Richard, thanks for the question. The research you propose sounds like an interesting one. As for vibrations affecting the growth of mold on bread, unless you use a frequency and sound power (volume) sufficient to actually damage the individual cells in the hyphae (a strand of the fungi) the likely outcome is to give the appearace of actually accelerating the growth. What will happen is that the vibration will increase the spread of the spores which will then grow and make it appear that the mold subjected to the vibration is growing faster.
Another thing to consider is that the most common molds found on bread are species of Penicillium or Rhizopus. Both of these are very fast growing molds and produce tremendous numbers of spores. These molds are know asthma triggers, allergens and in some cases of high exposure can cause illness. So be very very carefull when handling your experiment - work closely with your teacher on this one.
Instead of using vibration (which will create large amounts of airborne spores) as your testing criteria you might want to consider comparing growth under different type of lighting (regular light, no light and 'black light' (UV). To do this you would let some mold grow on a single piece of bread and then transfer some of that growth from one of the colonies (preferably a green one) to several other slices of bread. The transfer can be made using a tooth pick and just touch the original colony with the toothpick and then touch the tooth pick to the'clean' slice. Make up at least three slices to be grown in each test condition (ie. three in the regular light, three in the dark and three in the 'black light'. Keep them all at the same temperature and at the end of say 5 days, carefully (without touching the colonies) measure the diameter of each.
Good luck on your experiment and please let me know how it comes out. If you have any questions please contact me.
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